Helena first meets Dinah Lance in issue #9 of the Black Canary series of 1993.

From the first issue, we can see that Helena was aware of who Dinah was, and is eager to be friends with her. 

Dinah on the other hand, is a bit more reluctant to reciprocate the affections (it must be coz of all dat spiky hurr). However, she eventually comes around. 

The origin of their lifelong friendship began in this issue, and we see how it was easy for the two of them to make this transition, and to build upon their relationship, in Birds of Prey.

It’s also quite sad that these two women are no longer in the DC universe as we know it, and that this wonderful relationship is one of the many things missing from the current status quo.