Ginga Hyouryuu Vifam 13

Thirteen children escape their colony planet after an alien attack and travel through space aboard the Earth military training ship Janus. After encountering incidents such as protecting an alien baby and meeting the enemy refugee protection organization Lapis, they head towards the planet taut, where their families are being held captive.

(Source: Sunrise World)

Note: This TV series was produced not as a sequel or spin-off, but as a new series that covers a side story happening adjacent to episodes 22-26 of the previous series, it depitcts the 13 characters on their journey in a fresh way, a nostalgic sight for Vifam fans.