The 71-year-old singer's children Carnie and Wendy, with ex-wife Marilyn Rovell, say their father is avoiding a tour that would mark the 50th anniversary of the band's hit song 'Fun, Fun, Fun' but insist he is healthy and happy.
Carnie told The New York Post newspaper: ''He is 71 and is doing okay. He is laying back a little bit, which is about time. I want him to do that.
''He has been on the road for 15 years, and he has continued to do whatever he wants.
''I like to make him dinner and hang out, but I want him to slow down.''
Meanwhile, the sisters, who also found fame in the band Wilson Phillips with singer Chynna Phillips, are annoyed by comments made by Yardbirds star Jeff Beck, who recently went on tour with their dad and said he was ''a bit of a nightmare'' and questioned his well-being after he endured years of drug and psychological problems beginning in the 1960s.
Jeff said: ''He doesn't speak. He's clearly in need of attention. But that's just my opinion.
''For four days I sat there and didn't even know Brian was in the room. He was so quiet, he never uttered a syllable.''
Carnie was unimpressed by his comments and said: ''Did he have a beer or what before he said it? It is crass and out there. I thought they had a good time on tour.
''When they were on tour I saw my father every single night onstage with Jeff. He had to sit in his chair to watch him, and when he played 'Surf's Up' my dad was in awe.''
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