"David and Victoria are still scratching their heads as to what is the perfect present to give them," says the source. "It's pretty damn hard finding the ideal gift for Tom and Katie."
After all, the star couple are having a fairytale wedding – which will reportedly take place at the Castle Odescalchi outside Rome amid friends and family, including their daughter, Suri, and Cruise's two children from his marriage to Nicole Kidman, Connor, 11, and Isabella, 13.
Another item still up for consideration for Victoria Beckham – what to wear to the black-tie ceremony. The fashionable former Spice Girl is still choosing between six or seven outfits for the nuptials, the source tells PEOPLE.
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"I'm easier (to shop for) – you can get me a bubble bath I'm okay – but I don't know what to give them," she said.