paranormal activity - at home

Last night, we were at our balcony, talking and just chatting, me, my brother, sister in law and the kids.. our kids were playing as it was a bit early... then my nephew, 3 years old was playing too when he suddenly cried out that someone is out there, he was pointing at the backside part of the house where my brother keep his fighting c*cks.. but it was dark at that side and a possible intruder is out of the choice too as it was a dead end and no one can go over the fence. My nephew was so scared as he was shaking, he keep on hugging my brother since he was that scared. He said he saw some guy in green! My cousin checked and no one was there. My sister in law then said that happened twice as last monday night my nephew saw someone again, that same guy in green! It was so creepy knowing some ghost might be at our home!! My daughter also had this experience in our bathroom, the shower curtain i put was a bit too short so when you shower you could see our legs...then one time we both were outside the bathroom with the door open when she cried out, mommy who is inside, i saw some feet! i just told her to stop, it was just your imagination as i do not like her to get creeped out as i was also scared lol.. i just put these things at the back of my mind and i hope nothing else will happen.