I will give some advice to protect myetherwallet. I also use these tips to secure myetherwallet. You should not give your private key to others, including your siblings. I keep a private key on my pc that I alone know. I do not store it in google drive, dropbox or other online storage media. Never insert a private key into a website other than MEW because it could be a trap of hackers. You should always check the authenticity of MEW web address, it could be a web phishing that has a web look like mew. It could be another trap of these irresponsible hackers. Then, use the Chrome Browser Extension EAL or MetaMask to block malicious sites. Always check the URL in Browser Bar:
https://www.myetherwallet.com. and always make sure that the bar is green and says MYETHERWALLET LLC [US].