Portia de Rossi hired a skywriter to mark her wedding anniversary

Ellen tweeted a picture of her and Portia beneath the sky, writing: "

"Look what my wife did for our wedding anniversary."

The declaration of love comes amid speculation 41-year-old Portia's marriage to Ellen, 56, is on the rocks following the actress' recent stint in rehab, but sources have insisted the pair have been working things out.

One insider said recently: "They've had their ups and downs. Portia has been very outspoken about previous issues, like her eating disorder, and she's good at seeking help when she needs to. They've worked out difficulties in the past, and no doubt they're trying to work out any problems right now."

And it was also claimed the pair were planning to celebrate their anniversary with a party.

The source said: "They both love to celebrate special occasions and holidays, and their wedding anniversary is no different. They usually celebrate with a big party and invite a lot of friends. They really are a lovely couple. They enjoy being married, and it shows."