Do i need to pay for a babysitter for oot guests with kids?

I'm having no kids and not paying for child care. If you would like to and can, I think that is fine but definitely not necessary or expected.

It would be nice, but it's not a necessity.

You can if you want to since its only 1 child, but I had a ton of OOT (actually, out of state) guests and we did not invite kids other than bridal party. Two guests still brought their babies, but it didn't affect the dinner count or chair count at all. (We also never specifically stated "no kids" anywhere, we just invited parents only and hoped they'd get the hint.) I left it up to my guests to either leave their kids at home or hire a local sitter. My venue didn't have a space for a sitter, and we didn't have the budget. It's definitely nice to offer, but not required.

I agree it’s nice but not necessary.

We’re having adult only wedding with exception of 3 immediate family children. I offered all my OOT friends help with finding a reliable sitter, or sharing nannies that my local friends use & will be leaving their children with (who offered this as well), but nobody is expecting us to pay for it. I think OOT people appreciate your help with finding a reliable, trustworthy nanny, more than you paying for it.

You mentioned that the only OOT person with a small child is your cousin. If this was my case I would let her bring her child, if she prefers (if this affects only 1 child).

It might be a nice gesture but I wouldn't feel obligated. We are paying for a sitter to stay at the venue (we have a second, small room across the hall where we plant to set up kids activities) to watch our ring bearers (my 2 nephews age 8 & 3 and his nephew age 8) during the reception. The 2 older boys are old enough to be self occupied for the most part but my brother and SIL have a tendency to "disappear" and I don't want my parents to feel obligated to play babysitter. FH's BIL is also just a terrible person and tends to start fights with his son for stupid crap so if I can keep them separate there is a better chance of getting through the night without FH's nephew having a complete meltdown. Outside of that, we will provide guests with reputable sitters but it would be their responsibility to hire them if that is the route they want to take.

I was considering hiring someone for the 5 infants I will have at mine. They’re going to be there for the ceremony but I don’t want their parents to have to leave early.

I think it’s a nice gesture but definitely not necessary.

We are doing no kids. I'm offering childcare mostly due to the fact that I want my brother and SIL to attend the wedding. Two of their three kids are in the wedding as well, but I just didn't want the excuse to be because no one could watch their kids. I also have a bridesmaid who has three kids herself, so I wanted to extend childcare to anyone who can't find a sitter or coming from OOT. FH has a lot of OOT family, which right now literally none of their kids are on the guest list (I guess FMIL didn't think they would bring them), so if the OOT guests want to bring them, they will have to stay in the "nursery" (rooms where the childcare will be). However, childcare is not a necessity to offer. I had planned on hiring some people I know from HS who are full-time babysitters, but my bridesmaid (and hair dresser) said her mom and aunt would love to do it for free (however, I will be compensating them because it'll be a longgg day, haha).

OOT guests pay for their own child care, unless you have engaged pros to work with a group of children from different families. Like, some people have an activity area for kids. But childcare is a parental responsibility, not a function or party host's .

Personally, if you can cover it, I think you should, especially since she's from OOT. Since it's only one family, it shouldn't be that costly. However, I don't think it's technically your responsibility. I definitely recommend that you do your due diligence in finding a reliable sitter, though!