okay he may have not been getting the proper amount of calcium. calcium deficiency will explanation them to get weak limbs. what where on earth you feeding them and what kind of set up do you have? such as lighting heat etc. another thing that could have happened is that he have a blockage... it is very important to soak them in reheat water to help them poo i soaked mine once a week. well add on some more details on how you cared for them for us to help see what it may have be. you need to do as much research on them and what requirements they need. when you feed your beardie you entail to dust your crickets with calcium powder or get gut laod for the crickets (a vitamin suppliment that the crickets put away and make them more nutritional for the beardie) and do not ever use crickets from your yard or outside they can own pesticides on them that will kill your beardie, and when you feed veggies never ever feed rime burg lettuce there is no nutritional value to it, you need to nurture baby spinach, romaine lettuce, squash, red cabbage,carrots,broccoli,a large mix of things that hold lots of vitamins in it. he needs the fresh veggies daily . i hold a place for the crickets to hide so that the crickets last a week and he has fun "hunting" the crickets. also he wants fresh water daily. well i hope i help.
you probably gave him crickets that were too big and caused impactation. they should be no larger than the space between their eyes. research!! dont win anymore, they obviously arnt the right pet for you if 2 have died
Like another has said, it can be many different things that cause your beardies to die.
My recommendation to you is to do research and get everything set up before you purchase another beardie. Even though they are unbelievably hearty reptiles they can die from the littlest things.
Last note, ignore the sacratic, uneducated responses, such as "you don't have a clue." That contributor post nothing but sarcastic and unapprised responses and should be banned from posting on the board.
Sorry to hear about your beardies deaths and longing you the best.