Invalid parameter when using formula with empty date field

Platform discussions Special workflows & use cases
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1

I want this formula to calculate the age of a child only if the Child 1 DOB field is populated. It works fine when the DOB field is populated. When blank I keep getting an invalid parameter error.

Any thoughts on how to resolve?

IF(NOT({Child 1 DOB} = “”), ROUNDUP(DAYS(TODAY(), {Child 1 DOB}) / 365, 1), “”)

2

What about something like this?
IF({Child 1 DOB}=“”,“”,INT(YEARFRAC({Child 1 DOB}, TODAY())))

I got the idea from @JCorrell (Jim - The Monday Man).