Tropical Storm and Thunder Storm are siblings that bounded over a bad childhood caused by a neglectful parent. Thankfully they had each other. And made a family of their own to make up for the bad memories. Throughout the years they stayed really close to their more loving parent, Lightning Storm, until, well...
Tropical was in heat and Thunder was out of commission. And mama happened to be well endowed full of love for her daughter.
Monsoon Storm is raised and taken care by Thunder and Tropical together with their own foals, never told that they are technically his own siblings' stepdad and brother. Is that right? Monsoon doesn't seem to care much, he still loves his siblings, no matter their relationship
Also say hi to little judgmental Aster in the second slide for me <3