The 66-year-old rock musician is married to Humphreys, 35.
"Once in a while, she gets mistaken for my daughter," Wood told the British issue of HELLO! magazine.
Recalling an incident, Humphreys said: "We were getting off an aeroplane just recently and someone said loudly, 'Oh my God, it's Keith Richards.' Then to make it worse, they asked 'Are you his daughter?' I was thinking 'Please just stop talking.'"
For Humphreys, the 31-year age gap is not something to "bother" about. She says those who know them as a couple don't "flinch" about their relationship.
"The fact is, there is an age gap so it isn't unreasonable for someone to think that. It seems to bother other people more than it bothers us and then you have to remember you don't know those people because the people who do know us, don't flinch about it," she said.
--IANS (Posted on 18-12-2013)