You do know that the gift to your child is not deductible, right? Not sure why you are worrying about the postmark for the check for 2022. Gifts to individuals are not deductible.
GIFTS
Money that you receive as a gift is not taxable income to you, and you do not need to report it on your income tax return. Money that you gave as a gift to someone else is not deductible for your taxes.
Turbo Tax does not support the gift tax form 709, but here is a link:
https://www.irs.gov/pub/irs-pdf/f709.pdf
https://turbotax.intuit.com/tax-tips/estates/the-gift-tax-made-simple/L5tGWVC8N
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
