Fed up of back chat arguing and shitty disrespectful behavior

[Brighteyes27]

Fed up with disrespect and back chat from DS 13 and DD 12 and the carry on at bed time every blooming night. Advice please about how to tackle their behavior.
Both can be lovely individually, at school and to other adults and occasionally to each other but recently the back chat has got much worse. To make matters worth elderly MIL has been staying with us for an extended stay over Easter which hasn't helped as we have had to tailor whatever we have done or not done to accommodate her and them. They have been mainly lovely to her but their cheekiness to us and back chat has got very much worse especially at bed times. How do we solve this without inflicting physical harm as we would have both got a smack if we had dared to speak to our parents like this? We need to nip this in the bud incase it gets any worse. Any advice.

[specialsubject]

Consequences. Guessing overuse of brickphones which tends to cause brattness. Get rid.

Also add the carrot, do more together - and dont you be staring at your brick either. See so much of that and it shouts 'my kids bore me'.

[ImperialBlether]

Family meeting. Don't smile, don't laugh, be really serious. Tell them you've absolutely had enough. Tell them exactly how awful it is to live with them while they're like this. That they have a choice - an unhappy home, loss of privileges, unhappy parents, no friends allowed to visit, etc, or they can show a bit of respect to everyone in the house and behave themselves. Kids behaving badly can destroy the whole family's happiness - they need to realise that.

[Brighteyes27]

Thanks wewill have another family meeting when MIL goes home she's been here for 10 days as FIL passed away beginning of Jan. In the meantime I have confiscated their iPads. Admittedly we haven't done as much together as a family as DH has just been made redundant but prior to that he was worrying about his job. But to be fair most times I think they would prefer staring into space on iPads than doing anything with us also have a battle over homework
every weekend and I don't like going off anywhere until I know they have made an Effort and are either well on with it or have finished it. They know this and still they stall argue don't play ball etc.