Nick Lachey and Vanessa Minnillo are planning to marry in April.The former 'The Newlyweds' star - who divorced Jessica Simpson last year - has proposed to the MTV presenter and she is telling friends to keep April free. A source told the National Enquirer magazine: "They're moving forward with plans for an April wedding. Since they both love Baja in Mexico it will probably happen south of the border, where they first fell in love."When he married Jessica, Nick had a big splashy Texas wedding with all the trimmings."It kicked off their highly rated MTV reality series 'Newlyweds' and began their life in a fishbowl. This time he wants something a lot simpler, so they decided on a low-key affair."Nick, 33, announced his split from Jessica in late 2005 and began dating 26-year-old Vanessa last summer.The source added: "Nick's known for a long time that Vanessa is the one. At first she held out. But in time she began to realise Nick was the key to her happiness and couldn't imagine like without him."Vanessa feel's she's got Nick just where she wants him. Jessica is finally out of the picture for good. And now the two of them are ready to begin making a new life together."