Thanks Dieter. Yes, I agree. My reservation is: If the father had stopped using Strauss at the time of his daughter's birth (she was born in the US), without a birth document, we can't know for sure what the LNAB actually is. In that case, is it better to leave the profile's LNAB as "unknown" or take a best guess. My inclination is to do what you suggest, but WikiTree tends to be pretty fussy about LNAB and I'm always uneasy about what to do in cases such as this.