The McCartneys Come Together for stroll in the park

But the former Beatle showed it was Good Day Sunshine after he chased the blues away with his daughter and grandson.

The 64-year-old pop legend spent the day in London's sun-blushed Hyde Park with two-year-old grandson Miller and fashion designer daughter Stella, 35.

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After all his recent divorce woes, Sir Paul seemed in a relaxed mood as he enjoyed an afternoon in London's Hyde Park with daughter Stella and grandson Miller

Sir Paul, who pushed toddler's pram along, even plucked a flower from a plant he was passing by to give to little Miller as a keepsake of their day out.

Sporting open-toe sandals and slacks with a jacket casually slung over his shoulder the rock-star grandad looked like he didn't have a care in the world.

No-one could blame the star if he bore a frown at the moment.

Last week it was revealed that his predicted wealth on the influential rich-list had nosedived amid expectations that he will have to pay out £100m in his divorce settlement to Heather Mills.

Experts have shunted him down from being the 65th richest person in Britain last year to 102nd this year. He is now valued at £725 million.

Meanwhile his former wife has become a reality TV star in the US after a string of performances in the U.S. version of Strictly Come Dancing. She is still in the contests and has won rave reviews.

Toddler Miller is Stella McCartney's first child by her husband of three years, magazine publisher Alasdhair Willis, 36, after the couple wed in 2003.

In December, Stella, gave birth to her second child, naming the child after her late mother Linda - Bailey Linda Olwyn Willis.

Sir Paul has four grandchildren in total. His other daughter Mary having two sons named Arthur and Elliot.

After his first wife Linda died in 1998, McCartney began a relationship with Mills which saw them married in 2002 and the following year she gave birth to their daughter Beatrice Milly McCartney.