my x husband is Catholic, but while married, we agreed we could raise them as Jews. i always felt so very guilty for having both holiday decorations set up. But the kids LOVED it & i do not blame them, twice the fun.
Now i am divorced & the kids & i celebrate Hanukkah only. The kids have the choice of opening a gift or two each night, or all at once. They’ve agreed, for the last 3 holidays since the divorce, a few each night. And they have told me that they love Hanukkah more, because waiting until night fall for 8 days, with gifts piled high, is a fantastic test in patience & reward.
The kids still celebrate Christmas with my x & his family & they do enjoy that as well. it is very different from when they celebrated both…back then, the kids had a choice of opening a gift a night for Hanukkah, or open all the gifts under the Christmas tree. They always picked Christmas morning. Now having the both holidays spent in their proper way, the love it! as any kid would.
bottom line? screw guilt, enjoy what makes your young children happy. Maybe just offer a choice of which holiday they would like to open gifts on…more often than not, the answer will be BOTH!