I think one of the things yiu are struggling with, that others haven’t quite understood, is that you can’t enter the details of 3 adults into the boxes on THS when setting up your profile, and you are worried that you might br breaking a rule by not separately entering details of each member of the family?
THS was originally set up to have one account holder, and you could add in s second adult, who was not identity checked. More recently, THS introduced the “co sitter” add on, where the second adult can also be identity checked. Accounts with this add on are able to book sits that overlap by up to 2 days. However it is not necessary to have the “co sitter” feature to have 2 (or more) adults in the party. It only exists to allow overlapping sits. If you don’t want to do overlapping sits, you don’t need the “co sitter” feature, you can still add the details of a second adult to your profile, but they won’t be identity checked.
If you can only add one additional adult to your profile, you can introduce a third adult in the text of your profile, and also make this clear in your application.
I sit with my 2 teenage sons, now aged 17 and 15. My oldest won’t be a child this time next year, so I guess I can add him in as a second adult. I won’t add the “co sitter” feature because we don’t intend to do overlapping sits (and I think he would have to be 21 to be an official “co sitter”). Once my younger son is 18, we will also be 3 adults, so I probably won’t be able to enter his details separately and would just have to write about him in my profile.
Others have already mentioned that there are less sits available to families with children, or for bigger groups, whether they are families or groups of friends. However they do exist! My advice would be to look for sits with multiple pets where more pairs of hands is an advantage, apply for last minute sits, short sits, and sits at popular times when hosts have to compete for sitters. This was our strategy to start with. We have now done over 50 sits. Look at the profiles of past sitters for the sits you are thinking of applying for. If they gave previously hosted families, you have a better chance of success.
It’s all about finding the right match. If there are people who are put off by the non traditional make up of your family, they wouldn’t be a good match for you. Don’t be too discouraged by rejections, they are part of the process of getting started on THS. Many successful sitters were rejected multiple times before getting their first sit.
Good luck!