Control over screen time for multiple devices for each kid via the parent's phone

When I set up the screen time I feel a difference between a single and multiple devices for a kid. With a single device I can either control screen time from my phone or their phone. I can also approve screen time requests from both. But when my kid gets an additional device, I can only control one of them. For example, I had control over the iPad, but when my son got an iPhone and logged in with his profile, I no longer get screen time requests and I have to approve them directly on the iPhone instead on my phone. I can also only monitor the stats on my phone for one of the devices (the iPad, i.e. the first one).

Is there a way to set up control over multiple devices via the parent's phone?