Id it’s something wrong, you are in a spot for free ice cream for many years. Nice score for both of you.

Did the kid look like him?

Maybe he owns the shop, and your sister doesn't know he quit his $$$ job and invested their life savings in to his dream of owning an ice-cream shop. He was excited to tell his employee about the new ice cream flavor he ordered.

Invite her entire family there for ice cream.

Just ask him. Regardless of why he did it, chatting up a completely random other family and not sitting with his own family is rude and I would present it like that.

If this happened to me this is what I would say:

"Hey Bob, what was the deal at the ice cream shop the other day? I was kind of hurt you didn't sit and chat with Lucinda and I and the whole thing seemed weird? How do you know the girl working there? Is she family? Who was the boy you were talking with? The whole thing was just confusing and I was expecting you to sit with us once we saw each other. Can you shine some light on the situation for me?"

who’s hotter?

So much loaded language. I'd just say something like, " It was nice running into you at the ice cream shop. It's too bad you didn't have the kids with you, we would have loved to have seen them too. Good luck while sis is out of town. I know kids can be a handful. "

It gives him a warning without swinging a verbal sledge hammer around.

If I were your sister, I would want to know.

Anonymous wrote:I'm super close to both of my brothers in law so I can't even imagine running into them and not sitting with them. That is super odd to me. If it were me, I would just ask my BIL straight out. I don't play games.

I’d do this too. My sister can be difficult and I like my BIL even though we are not that close. He’s come sit with me if he saw me in public. I’d say something like “hey, this has been bothering me. You seemed surprised to see us then didn’t sit with us at the ice cream shop. I assumed you would come over but you didn’t. Who was that family? I didn’t recognize them.”

Anonymous wrote:If you can afford it hire a PI to follow him around and see what he/she can find out, before saying anything to your sister and starting a brawl in the family. It's weird that he pretended not to know you and went to sit by other people. I'd be mad at my BIL if he did that. Maybe the girl doesn't know he's married? Other possibilities: Maybe she's the daughter of an old friend of his? He thinks you're nosey so he didn't want to introduce you to her even thou nothing is going on? Maybe she works in his office and this is her side gig? There might be an innocent explanation, even if it looks and feel like something is going on. Jeez, I've been frozen out by acquaintances I don't give a damn about and thought nothing of it, but I would be offended if my BIL did that.

If you can afford it hire a PI to follow him around and see what he/she can find out, before saying anything to your sister and starting a brawl in the family. It's weird that he pretended not to know you and went to sit by other people. I'd be mad at my BIL if he did that. Maybe the girl doesn't know he's married? Other possibilities: Maybe she's the daughter of an old friend of his? He thinks you're nosey so he didn't want to introduce you to her even thou nothing is going on? Maybe she works in his office and this is her side gig? There might be an innocent explanation, even if it looks and feel like something is going on. Jeez, I've been frozen out by acquaintances I don't give a damn about and thought nothing of it, but I would be offended if my BIL did that.

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Mention it to her when he is in the room.

This.
“Hey sis. Did Larlo tell you we ran into him at Scoopz? I wish I’d known he was besties with the girl behind the counter. Seemed to know her family that was there. She could’ve given me the family discount on that mud pie ice cream I love. What was her name, Larlo?”

THIS. ALL OF THIS.

OK, so this is the worst idea ever. Ever.

MYOB is the only course of action here. He isn't having a fling with the ice cream girl. Stop jumping to conclusions.

What’s the harm? If he’s not doing anything wrong, then they’re just having a conversation.

DP. Girl, please. That recommended verbiage is loaded with way to much ammo for a trigger-happy sister ready to wreck shop off of general principle.

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Mention it to her when he is in the room.

This.
“Hey sis. Did Larlo tell you we ran into him at Scoopz? I wish I’d known he was besties with the girl behind the counter. Seemed to know her family that was there. She could’ve given me the family discount on that mud pie ice cream I love. What was her name, Larlo?”

THIS. ALL OF THIS.

OK, so this is the worst idea ever. Ever.

MYOB is the only course of action here. He isn't having a fling with the ice cream girl. Stop jumping to conclusions.

What’s the harm? If he’s not doing anything wrong, then they’re just having a conversation.

I'm super close to both of my brothers in law so I can't even imagine running into them and not sitting with them. That is super odd to me. If it were me, I would just ask my BIL straight out. I don't play games.

Anonymous wrote:That's very strange, OP. Just the fact that he'd stay in the same shop with you and your kid ignoring you but talking to another kid for 15 minutes is bizarre. I'd say something to my sister but she's not crazy and reading between the lines it sounds like you think your BIL is too good for your sister and possibly too good for you (his inlaws).

I agree with the first part here, that is so strange he would stay there and not offer an explanation. I would think if he was having an affair he would be trying to cover it up by immediately offering some excuse as to why he’s there, offer you some story about how he knows the people he was taking to.