Harris' partner, Burtka, also "has" two children from a previous "relationship".
I can't take some of the commenters here seriously between their use of language, disinterest in situation-specific facts (not adopted kids) and various realities like the gay men who did marry women and had children naturally and ended up in divorce, etc.
This is where their lackadaisical approach to the care and feeding of the culture for future generations has come back to bite. They act like they were powerless when they simply didn't care to take up the cause. This fight was really lost in the 90s and certainly by the time W was talking about a marriage amendment (conveniently for reelection) that never got close to reality. Taking the attitude "it'll never happen" and not getting involved as more and more ground was ceded... they have no right to complain.
Just like thinking not voting for Romney last month would teach everyone a lesson, they just put themselves further and further away from being "winnable" by campaigns... it's self-marginalization which in the end guarantees they will not be listened too if they are even heard. In the final analysis they get what they truly wanted: even more things to complain about.