Schlage deadbolt and multisensor problem

I’m brand new to this. Please be patient. My daughter needs a home security solution and asked me to help with it. I want to install a schlage smart connect deadbolt. I would also like to place a smartthings multisensor on the door to monitor the open/closed condition of the door. I then want to associate a siren with the multisensor so that it will sound if the door is forced open while the deadbolt is in the LOCKED position. My daughter is in a difficult situation. We’re concerned about her safety and are trying to do what we can to help her be more secure.
I was hoping that the smartthings hub might be able to use the condition of the schlage deadbolt LOCK/UNLOCK to arm and disarm the multisensor on the door. Is that possible?
she’s in a large old house and sleeps on the second floor. If someone forced the door during the night while the deadbolt is locked she would probably not hear a phone notification thus the siren idea. However we would only want the siren to activate when the deadbolt is in the locked position and the multisensor shows open door. we wouldn’t want the siren to sound when she opens an unlocked door. Is what I’m seeking possible? Is there a better way? Thank you for any assistance you can offer.

Okay so there are a couple of things you’re looking at doing here, let me try to address them individually.

If you’re using the Schlage Connect Deadbolt and you have access to rboy apps, you may not need a multisensor since the BE469 has a built in tamping sensor and a VERY 90 dB loud alarm/siren. The sensor can be configured at different sensitivity levels and different modes (alert, tamper, force etc). You can use a custom device handler and app like the Schlage Lock Alarm Mode and Sensitivity Change and Monitor which can change the locks tamper and sensitive modes based on various parameters (like hub mode etc).
Now you can configure the app to set the lock alarm mode to Alert (the lock beeps when someone touches the door) during the day when the hub is in Home mode, set it to Tamper mode (with medium sensitivity) when the hub is night mode (the built in alarm triggers and also notifies ST) and to Forced entry with high sensitivity when the hub is set to Away mode. The lock alarm is highly configurable and can detect a range of activity from a very simple touch the door knob to someone trying to break down the door, plus it sends a notification to ST (through the custom DTH) when it is triggered in any mode except Alert mode (see the lock manual for details).

The custom device handler also reports to ST when the alarm on the lock is triggered, so you can use a simple app like Smart Lighting or CoRE etc to trigger your siren when the lock reports that tampering was detected.

You can do all you need to do with just the BE469, a custom device handler and the appropriate app.

Now adding the door sensor can have other advantages where you can create a whole home security setup with the built in SHM app which can trigger an alarm if the door is opened at specific conditions or you can build you own security setup using the Intruder Alert with Alarms app.

You can start doing a lot more but your basic needs can be fulfilled with just the BE469, a custom DTH and a SmartApp. The additional siren and multi sensor opens up additional options and use cases for you.