How to create Parent / Child Structure in International Listings from Source Marketplace

Hi, My source marketplace is the UK and I used the Build International Listings tool to copy my listings for a number of European marketplaces. However, the BIL tool has not copied over my parent ASINs (I have 5 parents, each with 7 variations). This has caused a few instances where I have a different listing per variation. Amazon has then also split the reviews down based on the ASIN in that listing (which reduces down my review total).

Does anyone know how I can group these listings under 1 parent so that the variations all show together, instead of on individual listings?

Thank you