Melinda Gates has shared a Mother's Day message following her shock divorce announcement.

During an emotional tweet, the estranged wife of Microsoft co-founder Bill, said she was feeling extra appreciative for her three children as America celebrated the big day.

Melinda, 56, shared a throwback photo to Twitter featuring her and her three children — daughters Phoebe, 18, and Jennifer, 25, and son Rory, 21.

"I love being their mother," she wrote on Sunday.

"Whatever Mother's Day means to you—a day to celebrate a mom, honour a memory, or reflect on your own resilience - I hope your day is a meaningful one."

In a joint statement, the pair announced their separation on social media last Monday.

Close up of Melinda Gates
Melinda Gates says she found it hard living in Bill's shadow

It said: "After a great deal of thought and a lot of work on our relationship, we have made the decision to end our marriage.

"Over the last 27 years, we have raised three incredible children and built a foundation that works all over the world to enable all people to lead healthy, productive lives," it added, referring to the Bill & Melinda Gates Foundation, which they founded in 2000 and is now worth over $40 billion (£28 billion).

A source recently told PEOPLE that a "combo of things" led to the pair's split, and that recent timing reflects the fact that their youngest child, daughter Phoebe, is now an adult.

"It's absolutely because their youngest child is graduating from high school, and the idea was that they stayed together through that," the source said.

Melinda Gates and Bill Gates dressed in formal attire as they attend event
Melinda Gates and Bill Gates attend The Robin Hood Foundation's 2018

"They limped through until their kids were out of school like a lot of people."

According to a recent New York Times article, the Covid quarantine was a big adjustment for Bill and Melinda, who had spent the past three decades travelling around the world.

"Working from home — that was a piece that I think we hadn't really individually prepared for quite as much," Melinda told the outlet last October.

The Times piece also noted that Bill and Melinda had been growing apart for several years now, partially due to Melinda's struggles with being in Bill's shadow.

"I've been trying to find my voice as I've been speaking next to Bill, and that can make it hard to be heard," she wrote in her 2019 book The Moment of Lift .

Bill Gates and Melinda first met in 1987 after the latter joined Bill's company as a product manager.

It took them four months to begin talking to each other when they sat together at a trade-fair dinner in New York City, with Melinda reportedly saying : "He was funnier than I expected him to be."