2004–2006 Freddie was
conceived in late 2003 when his mother,
Little Mo Mitchell (
Kacey Ainsworth), is
raped by her friend,
Graham Foster (
Alex McSweeney). Her refusal to
abort the child results in the break down of her marriage to
Billy Mitchell (
Perry Fenwick). Little Mo stays with her sister,
Belinda Peacock (
Leanne Lakey), where she gives birth to Freddie. In November 2004, after Graham is sentenced to eight years
imprisonment, Little Mo and Billy make another attempt at their marriage, but they separate again after Billy admits that he is struggling to accept Freddie. Freddie then lives at the
Slater family household with Little Mo, his great-grandmother
Big Mo (
Laila Morse), his grandfather
Charlie Slater (
Derek Martin) and second cousin
Stacey Slater (
Lacey Turner). In February and March 2006, Freddie causes Little Mo much stress by crying a lot. He takes a trip to the park with Little Mo,
Jane Collins (
Laurie Brett) and
Bobby Beale (Kevin Curran), where Bobby pokes him in the forehead with a stick, and so Freddie is taken to hospital. However, the incident results in a visit from a health visitor. Little Mo thinks that the health visitor is accusing her of
abusing Freddie and becomes angry and hostile. Little Mo struggles to cope with Freddie when he begins
teething. In May 2006, Freddie is rushed to hospital, seriously ill with bleeding on the brain. A few days before the hospital admission, Little Mo admits to her boyfriend
Oliver Cousins (
Tom Ellis), who is also a
GP, that she sometimes gets very irritated with Freddie when he cries. When Oliver hears that Freddie's injury must have been caused by
shaking or rough handling, he admits what Little Mo has told him to a
paediatrician,
Briony Campbell (
Rae Hendrie), at the hospital. While the hospital believes that Little Mo may have shaken her son, Little Mo suspects that ten-year-old
Ben Mitchell (Charlie Jones) may have hurt him in some way, as they were left unsupervised together just before the incident. Little Mo confronts Ben and shakes him in irritation when he tries to run away. After extensive tests at the hospital, it is discovered that Freddie has a temporary
low platelet count, due to an infection, meaning that any minor injury could hurt him badly, as his blood is not clotting properly. Little Mo is no longer suspected of hurting her son. Freddie leaves
Walford on 26 May 2006 with Little Mo, who wants to start a new life in
Barnstaple,
Devon.
2022–2025 Freddie returns to Walford in September 2022, having decided to track down Billy, whom he believes is his father, after having an argument with Little Mo. Billy keeps up the pretence of being his father, to the annoyance of his partner
Honey Mitchell (
Emma Barton), so as not to hurt Freddie. Freddie starts to bond with his assumed half-siblings
Janet (Grace) and
Will (Freddie Phillips), and even steals a
fascinator for Janet, as she had her eye on it. When Billy is arrested for the murder of
Malcolm Keeble (
Christopher Pizzey) and needs money to hire a good
solicitor, Freddie becomes determined to help him out and gets a job at the local
fish and chip shop, having lied to
Bobby Beale (
Clay Milner Russell) that he has lengthy experience. Despite getting off to a bad start, Bobby gives him another chance and Freddie becomes an instant success with the customers. Freddie initially lives with his aunt,
Kat Slater (
Jessie Wallace) and her fiancé,
Phil Mitchell (
Steve McFadden) but after Phil tells him that Billy is not his father, a rift develops between them and he moves in with Stacey and her family, eventually joined by Kat's ex-husband,
Alfie Moon (
Shane Richie). Billy explains to Freddie that while it is true he is not his father, he wishes that he was and if it is not too late, would like to act as a surrogate father to him, which Freddie accepts. Due to his cheerful and laid back personality, Freddie soon settles into life in Walford and becomes close friends with Bobby as well as building solid relationships with Stacey, her mother
Jean Slater (
Gillian Wright) and Alfie, the latter of whom he later moves into
Harvey Monroe's (
Ross Boatman) former flat with. Freddie has sex with
Anna Knight (
Molly Rainford), knowing that Bobby has a crush on her. They try and conceal this from Bobby, but his father
Ian Beale (
Adam Woodyatt) exposes them publicly, leading to Bobby and Freddie falling out. In October 2023, Freddie walks in on his former schoolteacher
Theo Hawthorne (
William Ellis) trying to rape Stacey, and he violently beating him. He accidentally knocks Theo out unconscious and is arrested. After being released on bail, Freddie goes to stay with Little Mo temporarily. In May 2024, Freddie returns to Walford with his great-grandmother Big Mo. It is revealed that his feelings for Anna have developed during his time away from Walford. He tries to avoid Anna, and he reveals to her sister
Gina Knight (
Francesca Henry) that he is hiding his crush on Anna. Freddie discovers that Anna is pregnant with Bobby's baby and is planning on having an abortion. He agrees to keep quiet and grows closer to Anna when he supports her. They share a kiss just as Bobby walks in; he attacks Freddie and ends their friendship before leaving Walford. Freddie and Anna begin a slow-burning relationship, but Anna's mixed signals make Freddie believe that she does not love him. He sleeps with Gina but hides this from Anna, although Anna learns the truth when she overhears a conversation between Gina and their mother
Cindy Beale (
Michelle Collins). Anna ends their relationship, leaving Freddie upset. ==Reception==