Ever wondered who installed the battery pack on the Volt or ELR you are driving?

It turns out it is most likely the Evetta Osborne and Monique Watson daughter-mother duo. Both ladies work side by side at General Motors’ Detroit-Hamtramck assembly plant and GM said they have installed the lithium-ion battery pack on nearly every Chevrolet Volt, Opel Ampera, Holden Volt, and Cadillac ELR since production began.

In fact, per GM, apart from vacation days and an occasional sick day, the mother-daughter duo has installed almost every battery pack since the Volt was in pre-production in 2009. The ELR launched earlier this year. All told – including the Ampera version of the Volt sold in the UK – that’s more than 80,000 electric vehicles.

“We’re a good team and our relationship is secondary when it comes to performing our jobs – but it’s great to work alongside my daughter,” said Osborne, a mother of five.

Because the battery packs weigh more than 400 pounds each, automatic guided vehicles – robotic carts that use sensors to follow a path through the plant – deliver them just as the vehicle body structures glide into position overhead, explained GM. The carts then lift the T-shaped packs, and Osborne and Watson guide them into the chassis and secure each one with 24 fasteners.

GM stated it’s a routine the pair has down to a choreographed science on their small segment of the plant’s 16 miles of conveyers.

“We’ve been doing it long enough together that we anticipate each other’s moves,” said Watson, also a mom. “There’s a lot of non-verbal communication that we share when we’re working, but it’s also great to know my mother is there to talk with and share things with every day. The arrangement has absolutely improved our relationship.”

Osborne, who has worked at Detroit-Hamtramck since 1999, encouraged her daughter to apply, and Watson was hired in 2006. When Volt production was announced, they trained together in 2009 and were assigned to the battery installation station.

GM recently announced a $449-million investment to produce next-generation electrified vehicles at Detroit-Hamtramck and advanced battery technologies at the Brownstown Battery Assembly Plant. The investment includes $385 million in tooling and additional upgrades for Detroit-Hamtramck.