I totally get where you're coming from.
However my parents had a similar perception and it did effect me. Conversations, for example with the musical instrument we both played went like this:
"Oh yes Witchend does play. She's doing very well. But Witchend dbro plays and he's got the most wonderful technique. He works so hard and there's definitely something special when he plays." (repeat for anything else we both did)
Who do you get the impression is better then?
Well, I was considered to be quite talented when I started. I got to grade 2 after 4 terms, when I think the average is closer to grade 1 after 6. Dbro failed his grade 1 for the first time after 3 years and proceeded to fail it at least twice more before he passed it after he'd been playing for 6 years.
Result was I stopped playing. I regret it now because I think I could have been quite reasonable, but I really did feel why did I bother when that was the reaction I got. I wasn't really a go out for praise type person, but it was so downing that I felt uncherished.
I got that in a lot of walks of life that as an adult I can look back and realise that actually I was better than him, in some cases quite good, but I gave up because the impression I got from dm was he was much better than me, so I felt it was better to give up/not try than try and compete, because I always seemed to be considered the weaker.
It took me until I was an adult to realise that wasn't the case.
What I suggest is.
- Encourage dd2 to do different things. Dbro was always encouraged to do what I was doing so we were always in competition.
- Celebrate with both for what they've done. I remember getting into choir. I came home full of triumph. It was one of the first time I'd achieved something dsis hadn't already achieved. "I didn't want you to do that" was dm's reaction.
Looking back I think in the back of her mind was already "don't make too much as dbro won't get in" (very tone deaf). It's the only time she didn't act pleased with me to my memory, but it hurt. I didn't go back the next year, despite loving doing it.
- Recognise that your dd1 may well put effort in.
Looking back, I think dm thought things came easily to me. Some of the things I put a heck of a lot of effort in (eg making friends, none of us are very sociable, but I would make myself (often very nervous) go to things/support friends doing things I wasn't interested in etc. I remember bro being asked by one of the lads in his form to go with him and one other to do something he was always on at dm to take him. "Why would I want to go to that with you?" was his response.)
I felt I was punished for putting an effort in.
- Find things not connected with what they do to compliment them.
- Don't always make dd2 have second hand things. But also don't take things off dd1 because you deem them to be too young for them, even if she still plays with them.
- If dd1 has friends round don't make them take dd2 round with them. If dd2 has friends, don't let dd1 boss them around.
- look for strengths in dd2. Don't compare them. She will have strengths, just need to find them.
- Spend time with them equally as possible, Take one out for a drink and a cake at a café, and then take the other another week.
I'm sounding really negative about dm here, but she was a cheerleader of mine, and I knew she loved me and wanted me to do well.
But I think it also effected dbro negatively too. He thought he was really something special in these things, and a cut above others. Which made him act superior round his peers which didn't endear him to them.
He would also get very angry if dm didn't praise him to the skies, which then meant she'd do it doubly the next time...