Even though I'm not a parent, I thought I could contribute
I recently told my mother some of the stuff I would do as a kid. After about the third one, she turns to me and says, "Ya know, I don't think I want to know!" Examples include jumping off the step from the fifth step, doing flips on a trampoline...you parents don't want to know the rest.
A sense of humor is very important. Lots of laughter in my house. Unfortunately for my mother, most of it is directed at her.
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My dad came up with this thing when I was about three where he'd randomly say to me, "Let's laugh at Mom!" and we'd laugh for absolutely no reason.
I think my mom has had it rough with the two of us. I had a lot of health problems. Had to have my tonsils out in eighth grade after never having issues, then bleeding three days after the surgery. I have severe asthma, so there were so many nights where my mom would be up with me, and I'd be wheezing and we'd be contemplating trips to the hospital. I had pneumonia and two cases of bronchitis in one year in elementary school. I was hospitalized for my asthma in seventh grade after they called 911 from school. This past school year I was down at the ER three times, once from shooting myself with the epi pen after an allergic reaction and twice with my asthma. I started getting horrible migraines this past year. I've just had a lot happen that she's had to deal with (sorry dads, mine proved that you can be completely clueless about some of this stuff. Like mine: "She looks fine!" Mom: "Her chest is moving up and down meaning she can't breath!)
Then there's my brother. He has autism, which makes everything twice as difficult. I know she's constantly plagued by questions such as, "Will he graduate?" "How will he do next year?" "When is he going to melt down again and how hard will his sister/me get hit?" IMO nothing challenges a parent like having a child with special needs. He's got a long way to go, but my mom and dad have certainly done their best.
Things my parents did well:
1. They waited to have kids. They were married 9 years before I was born. This has led to a strong marriage. They also leave us at home some of the time and go off together. I think a strong marriage is important to raising kids. I know this isn't always possible, but it's made my life easier.
2. They wanted us to work hard, but at the same time not overdo it and have fun.
3. Family time is important. We go to baseball games, vacations, spend time outdoors, just try to be together.
4. Keeping lines of communication open. Sure, in middle school I went through the, "I don't want to talk to you." So my dad would talk about mailboxes. Why? Who knows. But it kept us talking even if it was nonsense, and when I had a bullying problem at school, I came to them right away and trusted them to handle it.
5. School first. Big one. I've now got a scholarship to go to college because of this.
6. If you do something, they will find out. So don't do it.
7. My mom is a big praiser. My dad is not. Mom wins on this one. Positive reinforcement is best, whereas not complimenting/saying "but you could have done this better" just tears down self esteem.