Age based on DOB; Accounts for leap years. Years old if >2, Months if <2 years old.

I am calculating the age of a child based on their DOB. I currently have =INT((TODAY()-'Qualtrics Output'!N3)/365.25) but I do not believe this accounts for leap years (our study is over 5+ years) and it also occurred to me that this formula will continually update. Basically, I need the child's age based on the day that the information is entered into Excel. To make things even more complicated, I need to calculate the age in months ONLY IF the child is less than 2 years old.