Concatenate multiple rows into 1 cell with carriage returns - slightly more advanced.

This is my first post so I would like to say helloto everyone.
Every Excel problem I've had so far I have found a solution on the forum but this time I'm stumped.

long story short, my website has many product images - up until now the parent image has shown above the children images. The site will only now show parent image. I have exported all product images (parent and child) and with the right formula could import the child images in the same cell as parent images. (1 product tested and it works)

VS Parent ID VS Child ID Parent Reference Child Reference Child Product Images
4573 99967 PE6030 PE6030White/ Black http://www.b-id.co.uk/images/product...5-17452700.jpg
4573 99968 PE6030 PE6030White/ Green http://www.b-id.co.uk/images/product...0-14622700.jpg
4573 99969 PE6030 PE6030White/ Light Blue http://www.b-id.co.uk/images/product...1-10525300.jpg
4573 99970 PE6030 PE6030White/ Navy http://www.b-id.co.uk/images/product...6-36322600.jpg
4573 99971 PE6030 PE6030White/ Orange http://www.b-id.co.uk/images/product...9-06755300.jpg
4573 99972 PE6030 PE6030White/ Red http://www.b-id.co.uk/images/product...7-92248800.jpg

How can you concatenate all child image URLs where parent ID (4573 in this case) is the same? The relevant urls need to be in 1 cell with hard carriage return between each one. there are 95,000 SKUs in my CSV export.

Thank you in advance for reading this and for any help.
Kyle.

2 product example.xlsx

This should be an example of 2 product lines as per export.