Gwen Stefani and Blake Shelton's best laid Christmas plans may have already hit a major snag.

Radar Online reports the newly minted couple has already pledged to be together for the holidays. However, Stefani has yet to work out plans for her three small children with husband Gavin Rossdale.

"Blake and Gwen have vowed to be together for Christmas," a source said, adding Rossdale isn't at all pleased with the idea of 11-year-old Kingston, 6-year-year-old Apollo and 1-year-old Zuma joining their big celebration.

"Gwen and Gavin are trying to determine if they can be under one roof on Christmas Eve for the boys to open presents," a source added. "If that is the situation, Blake has said he obviously wouldn't be there."

Word is if Rossdale had his way, the kids would be headed to Mammoth, California with him for the holiday. But reports are that scenario poses a problem for Stefani, given that is the very place the family used to spend the holidays, along with the nanny Rossdale is now accused of having an affair with.

The consensus seems it will be a win-win situation for the boys wherever they end up spending the holiday, given the way they have instantly taken to Shelton. A source adds he has already made a huge impression on them with his easy nature.

"Unlike Gavin, Blake likes to get dirty and is rough and tumble with them," the source added. "It's been a refreshing change around the house for Gwen, because she had been taking a lot of that on herself."

Stefani and Shelton recently went public with their relationship, after she split from Rossdale and Shelton announced his breakup with wife Miranda Lambert.