Someone told my mother that she can't put cream on her hands while fasting because it penetrates the skin. Is that true?

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

Applying cream on the face, hands, etc, while fasting is permissible since it does not enter the stomach. The fact that the skin absorbs creams does not affect the validity of the fast.

Allah knows best.