My adopted son was born in Canada (1997) to two Canadian citizens. His father is now a U.S. alien resident, and has married me, a U.S. citizen. After the Canadian biological mother relinquished her maternal rights to our son, I adopted him through the U.S. court system (in 2004). I know our son is a U.S. citizen by my adopting him, but does our son still have Canadian citizenship as well? Thanks.