53 years ago - Steve Dayton is born, the only heir to the Daystrom fortune.
43 years ago - 10-year-old Steve begins being plagued by his powers.
25 years ago - 28-year-old Steve befriends Niles Caulder, who begins to help him gain control of his powers.
22 years ago - 31-year-old Steve meets Rita Farr & falls in love. He becomes a part-time member of the Doom Patrol as Mento.
17 years ago - 36-year-old Steve begins to slip mentally when he loses Rita Farr in the battle that seemingly destroyed the Doom Patrol.
11 years ago - 42-year-old Steve suffers a severe mental break when the Doom Patrol finds Niles Caulder, but not Rita Farr.
1 year ago - 51-year-old Steve & Rita Farr discover that they are now very different people and choose to end their marriage.
The really fascinating thing about Mento is that he played a role in the team that was usually reserved for the female character in the books of his time. He had deliberately unreliable and often-mocked powers, was considered almost ancillary to the team, and was really only there as a love interest for a far more popular and well-conceived character. Comic book teams are full of characters like that, but it's usually a woman playing second fiddle to a guy. the fact that Elasti-Girl is the awesome centerpiece character and that Mento is the kind-of-pointless hanger-on is just fascinating.
We keep, him, though, because he plays a very important role in the history of the Doom Patrol, both in the development of the team, and as the guardian of Gar Logan. His declining mental state after the supposed death of Rita is just one more horrible thing to happen to Gar in his lifetime, but it's overcoming those tragedies that has made him heroic. Also, watching him overcome his mental handicap can, if written with an iota of taste and human empathy, turn Mento into a great character.
I also think it's interesting, inasmuch as the Doom Patrol are clearly a precursor to the X-Men, that Mento is clearly the equivalent of Cyclops. The X-men spent a lot of years treating their leader as a bit of a lame duck, and it's telling that the Doom Patrol, the team that they're based on, had the same characterization but applied more boldly.