Jessica Biel has posted a gushing birthday tribute to Justin Timberlake on Instagram.

Jessica Biel and Justin Timberlake [Instagram]

Jessica Biel and Justin Timberlake [Instagram]

The singer turned 39 on Friday (31.01.20) and his wife Jessica, 37, showed she has put their recent marital drama behind her as she took to the picture-sharing platform to post some sweet images of them together and share a birthday tribute.

She wrote: "Happy birthday to the most timeless man I know. You somehow grow up without growing old. We love you so much."

Last year, Justin issued a public apology to Jessica on his Instagram account after he was pictured holding hands with his 'Palmer' co-star Alisha Wainwright.

Justin - who has four-year-old son Silas with his wife - has spoken of his regret at such a "strong lapse in judgement" while under the influence of alcohol because he has embarrassed his family.

He said in a statement posted to on social media: "I stay away from gossip as much as I can, but for my family I feel it is important to address recent rumors that are hurting the people that I love.

"A few weeks ago I displayed a strong lapse in judgement - but let me be clear - nothing happened between me and my co-star.

"I drank way too much that night and I regret my behavior. I should have known better. This is not the example I want to set for my son. I apologize to my amazing wife and family for putting them through such an embarrassing situation, and I am focused on being the best husband and father I can be. This was not that (sic)."

Justin ended his statement by stressing he is still happy to be working on 'Palmer'.

He wrote: "I am incredibly proud to be working on Palmer. Looking forward to continuing to make this movie and excited for people to see it."

And friends of the pair say Jessica believes Justin didn't cheat on her.

An insider explained: "He's charming and outgoing. And obviously he drank too much this time, but Jessica believes he didn't cheat on her. She will stand by him.

"They will work through this. It was good that he issued an apology publicly but obviously the real work he is doing is in private and hopefully this was just a bad drunken night."

Another source said: "They are downplaying everything and trying to laugh it off as nothing. But it was definitely inappropriate and something that would make any wife uncomfortable. He had too much to drink and got carried away. Their marriage will survive.

"She is very good to him and he knows how lucky he is. He says it was not a big deal, they were all hanging out together and that's the end of the story."