The 30-year-old German lost to Williams in the 2016 Wimbledon final.
She said, "It's a dream come true, you are such an inspiration for all us, that's wonderful and I'm sure you will have your next Grand Slam title very soon".
We always knew Serena Williams' return from maternity leave would be big, but the way she's stormed the court to become an advocate for new mothers is something else.
There was to be no fairytale ending as Serena Williams sought to win a 23rd Grand Slam title just 10 months after suffering life-threatening complications from giving birth to her first child.
Kerber defeated Williams to win the Australian Open in 2016 and then, after losing here, lifted the trophy at the US Open.
The pair began working together in pre-season following Kerber's split from Torben Beltz, who had coached her for more than a decade.
"It was such an fantastic tournament for me". I just feel like to tell all the mums, like I had such a long struggle to come back and it was really hard, and honestly I feel like if I can do it, they can do it.
The husband of Serena Williams admitted on Sunday that he feared the tennis superstar would die after giving birth to their daughter past year.
And of course she had a message for mums: "I was playing for you today and I tried but Angelique played really well".
It is fair to say that Kerber was a step up in competition and it showed in her performance in a final.
"I knew that I had to play my best tennis against a champion like Serena", said Kerber, the first German woman to win Wimbledon since Steffi Graff in 1996.
She recovered from 2-0 down to lead 3-2, clinching the fifth game with a 125mph ace, the fastest serve of the women's tournament.
Saturday's victory was Kerber's third title at the Slams - all coming after her 28th birthday. In 2016, she beat Williams in the final of the Australian Open and again triumphed in NY to become the game's oldest first-time No. 1.
Despite the one-sided scoreline, both players inspired the world and Twitter most definitely took notice. All she could do was smile. It has been only 16 matches and four tournaments back. "I look forward to continuing to be back out here and do what I do best". I'm literally getting started.
After dragging herself off Centre Court, Angelique Kerber ran up to the players' box with one man in her sights.