I was watching a family of super quads (identical quadruplets) one day on TV. They were having their 6th birthday party and the parents said that they did not expect guests to bring 4 presents for each child. The guest can bring gift for the child they know - except for relatives, of course.

I'm of the same mind. I think if your child is only friends with one, then bring one present.  Unless the other child is baby and haven't had the chance to know anyone.

When my twins get to be preschool age and made different friends, I will only expect 1 present from whomever is friends with each one.

of course you bring the other kid something. it doesnt have to big. dont be fake and act like you dont know because you do. You'll feel better if you do. Imagine what the boys parents would of you for taking into consideration there son even though you didnt know him.

My daughter was invited to one of her friends parties & the friend has a twin sister. The party was for both girls with each inviting their own friends.

Some guests brought gifts for both girls while some bought only for who their child was invited by. Personally, I bought for both, but I'm also friends with the girls mother & know both girls.

As you do not know the other boy, I really don't think you need to buy him a gift. Both boys should be aware that they will each receive their own gifts from their own friends.

I would personally find out who this boy belongs too and speak to his parents and ask them what would they prefer, or ask the boys mother that you know..

Unless you give money, how are you to know what this other boy likes...

xx cazza

Who invited you? If it only had one boy on the invitiation then that is the one you should buy a present for. But if you wanted to get a card for the other one, then that would be acceptable.

I would always bring something for the other boy.  Just a card would do, I think.  Espcially since it's his b-day and you might end up getting along with him and his family.  Best of luck!