Hi there
I was a donor myself so its not exactly the same situation as yours but i did donate half my eggs when i cycled.. (but we are known and have to be by law for the child to track at 18years old) This is the law in the UK when you donate through the clinic the same as the sperm donor.
It is kind of left to the child (adult) if they decide to track you down later on in life.. I find this has put a lot of donors off hence why the waiting lists are quite long in the UK.
However I think in my own option if we ever needed to use donor eggs or sperm we would use them from someone we do not know someone the clinic provides..
The clinic run some really into depth tests, that if you were to do private would cost quite a lot of money so the safety checks are in place when you choose the sperm donor or egg donor you want.
Like someone else mentioned it could be a good thing using someone you know but on a down side they might try to have involvment into the childs life and to be honest i am unsure if yourself or your partner would want this??
To be honest not sure on how the law works and if there would be anything you could do to stop this from happening if he started trying to lay down on saying he wanted to see the child, how could you get around this not sure you could??
Lots to think about..
If it was me, then i would go donor route, that way YOUR child can decide IF they want to track the donor down .. If the donor was someone in the family i am not sure if this may cause problems further down for yourself and DP and the cousin and his family too.
(Could he really seperate his life from the babies life) i am not sure anyone could who was so closley involoved.
I feel that its a hard decision but i feel it is easier to use someone who isnt going to be around you or the baby should any live birth be as a result from the donation..
It may be a good idea to sit and write the pros and cons of using a donor you know and a donor you dont know and really thinking and talking it through with your DP..how each situtation that CAN and COULD arise if you used his cousin as the donor..
Good luck hun xx