Or just say the truth, "Larla, thank you for saying I remind you of your daughter. I'm sure she's great. I'm just a little burned out on this topic. I'm not sure you realize how much you talk about her."

Hi Betty..I have just 5 minutes before my meeting..What's up?

Tell her that you have been having some problems with your colon lately and the doctor hasn't been able to figure out what's wrong. Therefore you might have to get up at a second's notice and go to the bathroom.

Or tell her that you are expecting a phone call any minute from your sick mother's (grandmother's, great aunt's, etc.) doctor and you need privacy to discuss your relative's medical issues.