Lili and Ali are identical and wear different-colour boots to help their Maroubra Sharks coach identify them when he's giving orders during matches.

The Lee sisters and the Sharks are in Canberra for the Kanga Cup, joining 308 teams in the week-long tournament.

All 16-year-old siblings have arguments at home, but the Lees say they leave their family rivalries in the backyard to team up for the Sharks.

"Off the field it can get ugly, but there's no rivalry on the field. On the field it's just helpful to have them," Graci said.

Graci is a defender, Lili plays in the midfield and Ali is the striker who finishes the build-up work. But when their coach throws them into a midfield combination, he calls them the "lethal Lee-line".

Lili and Ali started playing soccer in 2010 and Graci followed two years later to form a sister trio. They were born in California and moved to Australia when they were 4.

"I started playing around 2012 ... then they kind of roped me into it after a while," Graci said.

"I think we're all better in our different positions, but our coach tends to put us in midfield and he's got this running joke, which he calls the 'lethal Lee-line'."

The Sharks lost their game against Tuggeranong United 3-0 on Tuesday and lost their opening game to the International Football School 7-0 on Monday.

They play Gungahlin United and the Monaro Panthers on Wednesday before finishing the regular rounds of the Kanga Cup against the Canberra United Academy on Thursday.

Games at Southwell Park, Harrison, Hawker and Downer were cancelled on Tuesday due to the poor weather as the day progressed, with the teams involved in cancelled games awarded a 1-1 draw.

Officials will make a decision on Wednesday on whether the fields will be reopened.