Alison Dubois has psychic powers, she mostly gets dreams of past events or future events, special messages from dead people, vague allusions, etc. Her abilities and range of said powers are not set in stone and various. She can see dead people, be possessed by them, see past events on a camera without tape, have 'special touch' like the Dead Zone guy. Her powers run in the family, from her half-brother to her daughters. Slowly in the past three seasons, her daughter's powers have been revealed.
Eldest daughter Ariel (Sofia Vassilieva) has been revealed to have telepathy, can slightly read people's minds, mostly numbers. She can guess numbers, like lottery numbers better. In one episode, she had dreams where she pictured herself in places but it was a living girl crying out for help from an abuser. Her father Joe mistakenly thought she could see ghosts, but as far as I, she hasn't demonstrated this ability yet.
Middle child Bridgette (Maria Lark) is much spritey, she is my favorite character. She can see dead people, most notably a child who she didn't know was dead, he didn't know either. Alison didn't have the heart to tell her the truth. Recently, she has had dreams from dead people.
Youngest Marie (Madison and Miranda Carabello) had yet to demonstrate any until Wednesday night's episode where she demonstrated an interesting ability. Joe was concerned when he saw her watching static on television, not any channel of static, but one specific channel. She would say, 'funny man.' Joe was afraid she saw dead people or that she was autistic but in reality she was watching a pay channel. She could some how see that the channel without paying for it. Cool power.