It's relatively simple to determine who controls a Bitcoin wallet. It's the person with access to the keys. 

If you do not make preparations for the future, your coins will remain inaccessible to your loved ones for eternity.  Or at least until quantum computing becomes a more viable thing. Make sure to state your Bitcoin in your will and testament, or at the very least, leave your key with a trusted party, in case of your untimely demise. Given the potential for price growth, I would rather be safe, than sorry!