Hi,
You could probably find a part time person interested is some of the hours you need
help. Most nannies will want a guaranteed number of hours per week, or a
higher rate per hour to compensate for the minimal hours. You may have more luck with a nanny looking for a few extra hours before their job starts. Evening will be trickier as most nannies don't get off until 6 or later.
How about a college student? Their schedules tend to be more flexible.
I actually have a part time evening position, similar to what you describe. The Dad works nights and the Mom works late or travels often.
I pick up the kids from activities between 5-6 or sometimes relieve the daytime nanny. I help with dinner, take care of baths, assist with homework for older kids and playtime/ evening routine for the toddler. This is all pretty typical for an after school or evening job.
Don't ever feel guilty for doing what is best for your family. Good luck in your search
If you cant find other Moms to help, please reach out. I will be looking to pick up a few additional hours soon, and would welcome the opportunity to discuss.