First off, I completely agree with @Rodafina
that the best way to know the answer to your question is to straight out ask him. It will be much more fruitful than speaking with strangers here and I also think it's a great opportunity for you two to grow closer, and signals that you have an interest in his wellbeing and are comfortable being vulnerable.
Since you asked, I will explain how I see your message here:
How are your mom and dad feeling? My daughter had a stomach flu last weekend. She’s better this week. She had to go to the sr though.
In this message, I just see one question followed by a statement. The question itself is manageable to me, though still a bit tricky as I actually don't know
how my parents are feeling. When it comes to the statement, well, I have no idea if I should respond to that, and what my response should be if I do. So, your daughter was sick and then got better. If she was still sick, I might know to say I hope she gets better (this is partly "scripted", even though it's true) and if you just said she got better, I might ask how she got sick, what happened or if I forgot something (though I might feel too awkward to ask if I was worried about having forgotten something you told me). As it stands however, it's just a closed statement. She got worse and then she got better.
This is actually a big problem for me if someone tells me about some hardship they are going through. "So, your aunt died? Well, erm, I'm sorry it happened....silence
...." My response always feels "canned", and I think the other person notices as well. This is even worse if I disagree with someone, like when they are criticizing someone I think is behaving reasonably since as I'm a terrible liar, and agreeing with them feels disingenuous but I'm also conflict averse, so I tend to just stay silent. This can also be a problem with jokes I find unfunny. People pretend I don't understand the joke, but often I do, but just don't have anything to say.
In terms of not initiating stuff and being passive, this was a major complaint of my ex. She had big plans for the next decade of her life, while I was content drifting through life and seeing where it takes me. She was absolutely right that I was way more passive than she, and hardly initiated anything, but I also didn't see the need to and still don't. If I am content with things how they are, and don't see a specific problem that needs solving, then what should I initiate, and why?
She wanted to go to a specific college, and I said that I would also be happy to go there with her, like she wanted. However, she wanted me
to really want to go there with her, and not because she wanted to go. Now, this was a bit of a conundrum for me, as obviously I hadn't been planning to go there before meeting her, but that's because I hadn't decided on any college yet, and now that I knew of one she was going to, it made the most sense to me. It was also a fine college, so I didn't see much going against the pick, but she still got annoyed about this as it wasn't "genuine" enough.
When it comes to the subject of the thread, I concur with what the others have said. Be direct, and don't expect him to take up any hints. I would never have admitted my feelings for my ex, and it took a year after we became friends for her to fall in love with me, and then she admitted her feelings towards me within a month.
Again though, don't mask for him. If you are struggling in constructing messages the right way, let him know, and ask for feedback. I see the willingness to make yourself vulnerable as a great strength. @Rodafina
mentioned in another thread how just being willing to say "I don't understand" has helped her a great deal. I think you should view that as a goal. Be willing to tell him "I don't know", "I need help" or "can you clarify this" when you feel uncertain.