Chicago PD "Tender Age" kicks off with Burgess and Ruzek spending time together. 

They've been hanging out a lot lately, but they aren't dating. Ruzek explains he's tired of the monotony as he almost crashes the car because a young girl is walking across the street in a trance. 

They rush to her side, but she isn't speaking. Burgess pulls her name from her shirt collar. 

When the duo arrives at the young girl's home, they see blood through the windows and realize that they're at the scene of a gruesome murder. Makayla's whole family has been gunned down; she's the sole survivor. 

Based on the bullet wounds, Intelligence determines that the attack had to be personal. 

A quick look into the family reveals that Makayla's uncle was a gang member, so the working theory is that it was gang retaliation. 

Upton gets intel from her CI, who informs her that Benny, the uncle, had beef with a man named Truman from an opposing gang. 

When they locate Truman, he immediately makes a run for it. 

Meanwhile, Burgess does her best to gain Makayla's trust in hopes of getting her to talk about what she saw. They bond over removing the crust's from their sandwiches. 

Truman doesn't want to implicate himself and gets a lawyer. Eventually, he informs them that he would never step foot inside that house because the little girl is protected. 

DCFS comes to get Makayla, but she clings to Burgess. At the foster house, Makayla reveals that she saw a woman inside her house. She ran outside as the woman was calling her name. 

The foster mom notices someone outside. Shortly after, gunshots ring out as masked intruders attempt to steal Makayla again. 

When DCFS tries to take Makayla into witness protection, Burgess informs them that she's not leaving the little girl's side. 

She and Ruzek stay with Makayla in the safehouse. When she hears a sound that reminds her of a gunshot, she wakes up in a panic and says that she's concerned "they" will come back. When Burgess presses, Makayla reveals the woman said she was with her daddy. 

Intelligence pinpoints an aggressive man named Tareek as Makayla's father. He was recently released from prison. 

Throughout his time there, he was communicating with a woman named Mia, who drives the same SUV that was spotted at the foster house. 

They bring in Mia for questioning and Voight informs her he's not falling for her "innocent" act. 

When she refuses to speak, Voight says they need to have Makayla identify the woman in a lineup. However, when Makayla hears her voice, she freaks out and runs. 

Burgess once again defends the little girl by informing Voight that she's not putting her through that. 

Her suggestion? Pretend Mia was idenitifed in the lineup to get her to talk. 

Burgess is in charge of questioning Mia and when she realizes the accomplice isn't going to cooperate, she scares her with the thought of being sent to a federal prison in Indiana where they have death row. 

Mia cracks and gives up Tareek's location. 

Intelligence ambushes Tareek, who explains that he just wanted his baby girl after she was taken from him. 

Burgess is able to talk him down and convince him to put down the gun. 

Makayla's aunt comes to pick her up. The whole ordeal makes Burgess question whether she could've been a mother and a cop at the same time. Ruzek informs her that she could have. 

Meanwhile, Upton gets a pretty impressive job offer from the FBI but turns it down because of Halstead. 

As they sit at the bar and share a drink, she tells him that it's been a long time since she saw him as just her partner. Halstead kisses her.