Gifts to family who are members of the Trust

My first question is to confirm which members of the family are automatically part of the Trust.

I’m the Trustee of a Hybrid Trust with both my wife and myself as beneficiaries.

I believe that the following people (besides ourselves) are automatic members of the Trust
– My and my wifes’ Parents
– My and my wives brothers and sisters.

If my brothers and sisters are married and have kids, are their spouses and children also automatically part of the Trust? I don’t think so, but just want to confirm.

Secondly, if I were to buy a family member a gift for their Birthday, does it have to be a gift (less then $100) for which I got a docket? Or, can I give cash of up to $100?

Thanks a lot.

Orion